Picking up a parked call

[Jeff]

When a call is in our shared parking, the recipient has to either push the Memory button corresponding to our call park and THEN pick up the handset or pickup the handset, press the "Cancel" soft button and then push the park button. If we try to pick up the handset and then push the call park button we get a dial tone and pressing the park button does nothing.

Surely this is a configuration error, so can anyone point me in the right direction to a solution?

Using T38g w/firmware v. 38.70.0.221